Advertisers try to distinguish between users who are browsing and those that are searching for goods and services. Users searching for specific goods and services may be responsive to targeted, contextual advertising, while those browsing without specific commercial goal may be targeted in other ways. However, it is difficult to understand the user's mindset in the online environment, which makes it difficult for advertisers to choose the most appropriate type of targeting for their advertising campaigns.
Web search engines typically are the starting point from which users begin their browsing for goods and services. Advertisers seek to take advantage of this and may pay for selected keywords that are correlated to advertising campaigns. As such, certain advertising may be displayed in response to the keywords being entered within a user's search query. In order to determine the success of an advertising campaign, a click through rate may be determined that represents the number of times an ad is clicked divided by the number of times the ad is shown. Higher click through rates are indicative of a successful advertising campaign, whereas lower click through rates may be indicative of a poor campaign that is not targeted at the correct user base.
While valuable, click through rates do not tell the whole story of the user's interaction with the search results page. For example, they do not indicate why the user clicked on a particular result, or which other results they considered, and did not click, before making a choice. These “abandoned,” un-clicked ads are highly indicative of user intent, however, click through rates and other measurement techniques cannot quantify user interests from un-clicked advertisements.